Membrane gas separation under magnetic field

Abstract

Apparatus, methods and uses for separating gas mixtures of at least two different gases under magnetic field and employing a membrane are described.

The invention claimed is: 
     
       1. Apparatus for the separation of a gas mixture of at least two different gases,
 wherein the apparatus comprises a first chamber and a second chamber, 
 wherein the first chamber has at least one inlet for feeding the gas mixture into the first chamber, 
 wherein the first chamber has at least one outlet for retrieving at least part of one of the at least two gases, 
 wherein the second chamber has at least one outlet for retrieving at least part of another one of the at least two gases, 
 wherein the first chamber and the second chamber are in contact and separated by a membrane, 
 wherein the membrane is surrounded by a magnet, 
 wherein the membrane is made of hollow fibers, 
 wherein the hollow fibers are made by spinning, 
 wherein the membrane is a polyimide-based membrane; and 
 wherein the hollow fibers have a circular wall and a void inside the circular wall, 
 wherein the circular wall has a wall thickness as determined by Scanning Electron Microscopy in the range of 130 to 160 μm. 
 
     
     
       2. The apparatus of  claim 1 , wherein the polyimide-based membrane has been carbonized. 
     
     
       3. The apparatus of  claim 1 , wherein the magnet is a permanent magnet. 
     
     
       4. The apparatus of  claim 1 , wherein the magnet is an electromagnet. 
     
     
       5. The apparatus of  claim 1 , wherein the magnet generates a magnetic field of 40 mT or more. 
     
     
       6. A method for separating a gas mixture of at least two gases which is carried out in an apparatus according to  claim 1 , the method comprising:
 passing the at least two gases through the membrane; and 
 separating the at least two gases of the gas mixture at least partially based on their selective attraction or repulsion by a magnetic field as they permeate through the membrane. 
 
     
     
       7. The method of  claim 6 , wherein the gas mixture of at least two gases is selected from the following mixtures of two gases: H 2 /CH 4 , He/CH 4 , H 2 /CO 2 , He/CO 2 , CO 2 /N 2 , CO 2 /CH 4 , and He/O 2 . 
     
     
       8. A method for separating a gas mixture of at least two gases,
 wherein the gas mixture is fed into a first chamber of a gas-separating apparatus via a first inlet, 
 wherein at least part of one of the at least two gases is retrieved from the first chamber via at least one outlet of the first chamber, 
 wherein the first chamber and a second chamber of the gas-separating apparatus are in contact and are separated by a membrane, 
 wherein at least part of another one of the at least two gases is retrieved from the second chamber via at least one outlet of the second chamber, 
 wherein the membrane is surrounded by a magnet, whereby an external magnetic field is applied to the membrane, 
 wherein the membrane is made of hollow fibers, 
 wherein the hollow fibers are made by spinning, 
 wherein the membrane is a polyimide-based membrane, and 
 wherein the hollow fibers have a circular wall and a void inside the circular wall, 
 wherein the circular wall has a wall thickness as determined by Scanning Electron Microscopy in the range of 130 to 160 μm. 
 
     
     
       9. The method of  claim 8 , wherein the gas mixture of at least two gases is selected from the following mixtures of two gases: H 2 /CH 4 , He/CH 4 , H 2 /CO 2 , He/CO 2 , CO 2 /N 2 , CO 2 /CH 4 , and He/O 2 . 
     
     
       10. A method of separating a gas mixture of at least two gases comprising:
 using a membrane surrounded by a magnet; 
 applying an external magnetic field to the membrane;
 separating the at least two gases of the gas mixture at least partially based on their selective attraction or repulsion by a magnetic field as they permeate through membrane, 
 wherein the membrane is made of hollow fibers, 
 wherein the hollow fibers are made by spinning, 
 wherein the membrane is a polyimide-based membrane, and 
 wherein the hollow fibers have a circular wall and a void inside the circular wall, 
 wherein the circular wall has a wall thickness as determined by Scanning Electron Microscopy in the range of 130 to 160 μm. 
 
 
     
     
       11. The use of  claim 10 , wherein the gas mixture of at least two gases is selected from the following mixtures of two gases: H 2 /CH 4 , He/CH 4 , H 2 /CO 2 , He/CO 2 , CO 2 /N 2 , CO 2 /CH 4 , and He/O 2 . 
     
     
       12. The apparatus of  claim 1 , wherein the membrane contains magnetic particles, wherein these particles are inserted in a matrix of the hollow fiber membrane or deposited on a surface of the membrane. 
     
     
       13. The method of  claim 8 , wherein the membrane contains magnetic particles, wherein these particles are inserted in a matrix of the membrane or deposited on a surface of the membrane. 
     
     
       14. The method of  claim 10 , wherein the membrane contains magnetic particles, wherein these particles are inserted in a matrix of the membrane or deposited on a surface of the membrane.